The invention relates to a process for preparing ethers such as tert-amyl-methyl-ether (TAME) and methyl-tert-hexyl-ether (MTHE). More specifically, the invention relates to a process using etherification reactors and catalytic distillation so as to provide excellent conversion rates from C5 and C6 iso-olefins to TAME and MTHE.
Various processes are known for using catalytic distillation in order to convert iso-olefins to ethers. Examples of such methods include U.S. Pat. No. 5,431,888 to Hickey et al., U.S. Pat. No. 5,536,886 to Tamminen et al., U.S. Pat. No. 5,313,005 to Smith, Jr. et al. and U.S. Pat. No. 5,689,013 to Jarvelin et al.
In conventional processes, it is difficult to obtain conversion of both iso-C5 and iso-C6 together. In addition, conventional processes provide some conversion, but higher conversion rates are desirable.
It is therefore the primary object of the present invention to provide a process whereby excellent conversion rates of iso-olefins to ethers are achieved.
It is a further object of the present invention to provide a process wherein C5 and C6 iso-olefins are simultaneously converted to TAME and MTHE, each with excellent conversion rates.
It is a still further object of the present invention to provide a process wherein advantages of both fixed bed etherification reactors and catalytic distillation are combined to provide excellent results.
Other object and advantages of the present invention will appear hereinbelow.